【正文】 a single chip microputer can accept, once every beat produces a pulse, make SCM generate an interrupt, every time, in addition to interrupt a count, every minute of the day on a heart rate sampling and statistics. Body temperature detection of the digital temperature sensor chip DS18B20 temperature measurement. Measurement data decoding, through CD4511 input digital tube display. Measurement data if the transfinite alarm. Blood pressure detection BP01 type pressure sensor is used to change the pressure signal into electrical signal through the opamp by ADC0809 is converted into digital quantity into single chip. If blood pressure transfinite alarm. The scheme can effectively, realtime monitoring parameters measurement of heart rate, body temperature, blood pressure these requirements, can achieve the indicators of system design, the design scheme is feasible. overall scheme 2 the hardware design master control chip MCS 51 The main function MCS 51 single chip microputer is the von neumann proposed by the classic puter architecture framework, that is, a puter is by arithmetic unit, controller, memory, input devices and output devices, a total of five basic parts. MCS 51 single chip microputer in a chip used CPU, RAM, ROM, timer/counter and multifunction I/O port, etc. MCS 51 single chip microputer system structure diagram is shown in figure 1. Figure MCS 51 single chip microputer system structure diagram By the graph, you can see that single chip microputer internal mainly includes the following several parts: (1) 8bit CPU (2) an onchip oscillators, oscillation frequency range of ~ 12 MHZ f, can have the clock output (3) 128 bytes of data in memory (4) 4 k bytes of memory on chip program (5) program memory address in the range of 64 k bytes 6 pieces of external data memory addressing in the range of 64 k bytes All landowners four 8bit parallel I/O interface: P0, P1, P2, P3 Today two 16 bit timer/counter Petname ruby interrupt system with five interrupt source The MCS 51 single chip microputer internal structure MCS 51 single chip microputer chip internal structure diagram as shown in figure 2. Figure 2 MCS 51 single chip microputer chip internal structure (1) the CPU The central processing unit (CPU) is the core ponent of the single chip microputer, is the width of 8 bits of data processor, can deal with 8 bit binary data or code, the CPU is responsible for the control, mand and scheduling of the entire unit system coordination work, to plete the operation and control of input and output functions such as operations. CPU is the core ponent of single chip microputer, is posed of unit and the controller circuit. Arithmetic unit circuit Arithmetic unit circuit including ALU (arithmetic logic unit) and ACC (accumulator), B registers, status register, register 1 and register 2 parts, such as the function of the unit is for arithmetic and logical operations. Operation circuit with ALU as the core unit, can do more than half a byte, a singlebyte and byte data arithmetic operations, including addition, subtraction, multiplication, division, decimal adjustment arithmetic operations such as and, or, xor, plementary and circulation, such as logic operation, the state by state register save operation results. The controller circuit Controller circuit including the program counter (PC), PC + 1 registers, instruction register, instruction decoder, data pointer DPTR, stack pointer SP, buffer, and timing and control circuit, etc. Control circuit to plete the mand and control work, coordinate with singlechip puter parts work normally. (2) the timer/counter MCS 51 single chip microputer chip has two 16 bit timer/counter and the timer 0 and timer 1. They can be used for timing control, time delay and count and test of external events, etc. (this design is through the timer/counter of encoder input pulse count). (3) storage MCS 51 series microcontroller program memory, including data storage and storage of its main characteristic is the program memory and data memory addressing space were independent of each other, physical structure is not the same. Except for the MCS 51 series (8031), there are four physically independent storage space: the internal and external program memory and internal and external data memory. For 8051 the chip of the munist party of China has 8051 RAM unit, including 128 units are occupied by the special register, after only the first 128 units for the use of the user. (4) parallel I/O port MCS 51 single chip microputer with a total of four eight I/O port (P0, P1, P2 and P3), each I/O lines can be used as input or output independently. P0 port for tristate bidirectional port, with eight TTL gate circuit, P1, P2 and P3 is twoway mouth mouth, load capacity of 4 TTL gate circuit. (5) the interrupt control system MCS 51 single chip microputer interrupt function is stronger, in order to meet the needs of the control application. 8051 a total of five interrupt source, namely the external interrupt of 2, 2, timer/counter interrupt a serial interrupt. All interrupts are divided into superior and inferior two interrupt priority level. Pin signal Figure 3 for the MCS 51 series microcontroller pins and logical symbols, DIP package them as the standard of 40 feet. Functional description of the pin is as follows: Figure 3 8051 MCU pin 1) power supply pin Vcc and Vss Vcc: power supply, + 5 v. Vss: ground terminal. 1. The input/output pin (I/O interface) (2) P0 interface ( ~ )。 8bit bidirectional I/O interface, for 1 ~ 8 feet. Quasi bidirectional interface is refers to the internal pullup resistor, the interface can drive four LSTTL (low power take off base tr